Prior to 2009, the breeding of Cape vultures at the NZG was assisted by means of artificial incubation and the hand rearing of chicks.

Then, in 2009, it was decided that the Cape vultures should be left to breed on their own. For a number of years they laid eggs and hatched chicks ... but some of the eggs and the chicks vanished.

Cape vultures lay and incubate only one egg at a time. It is only when the first egg breaks, or is removed, that they will lay a second one.

For this year's breeding season, the NZG's bird keepers decided to remove the breeding pair's first and second eggs and to replace these with dummy eggs to keep the pairs sitting on the nest/incubating.

Adjusting the humidity

Eggs are usually artificially incubated at a standard humidity and temperature, which is not necessarily suitable for the development of all chicks. Individual eggs sometimes require a different humidity during artificial incubation due to the varying thickness of the shell.

While the development of the Cape vulture embryo was being monitored, it became evident that egg number three required a lower humidity than the other two in the incubator. Therefore, the keepers either needed to move the egg to another incubator with less humidity, or lower the humidity in the original incubator, which would put the other two chicks at risk.

When it transpired that the egg could not be moved to the other incubator as it was unavailable, the bird keepers decided to return the egg to the parents to give them an opportunity to raise their chick, which is a requirement if they are to be released back into the wild.

As the pair had just a laid another egg, the keepers replaced that egg with the egg that needed to be moved instead of with a dummy egg. This had never been done before due to the fact that chicks and/or eggs had been disappearing from Cape vulture nests. Anxiety and doubt kicked in, but the team was adamant to put the birds' needs first - they deserved another chance to hatch and rear their own chicks.

The pair laid a second egg, which was replaced with the first egg. On 29 June, Grace Nkgweng, Abram Kupa and Delvina Mathye took the egg from the incubator to the vulture aviary. Upon arrival, Abram coaxed the sitting bird off the nest, Grace removed the second egg from the nest and Delvina put the first egg back in the nest while Abram made sure that the birds did not attack Delvina and Grace. As they were leaving, both the male and female immediately went to the nest to check the egg and the female settled on the nest.

The moment all were waiting for arrived ...

On 20 July 2012, Abram saw that the chick had hatched and hurried back to inform the team. The chick was named Malebo (which means "joy" or "happiness") by the vulture keeper, who commented that after three years of longing to see a vulture chick, the bird keepers were all honoured to be able to share this experience.

By Sarah Chabangu, Grace Nkgweng and Abram Kupa, Bird Keepers, NZG

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